Re: Stmmac: fix for hw timestamp of GMAC 3 unit

From: Giuseppe CAVALLARO
Date: Tue Jun 06 2017 - 01:43:56 EST


Hi Mario

thanks for your tests, and, at first glance, your patches seem to be sensible so,
please, send the changes as patches for net.git kernel.

Regards
Peppe


On 6/6/2017 12:11 AM, Mario Molitor wrote:
Dear stmmac maintainer group,

I have found an problem in stmmac driver of linux kernel and I hope for a fix in the mainline kernel.
At the moment I have two patch files which fix this problem for me.
The problem seems created with the commit d2042052a0aa6a54f01a0c9e14243ec040b100e2 and ba1ffd74df74a9efa5290f87632a0ed55f1aa387 has breakage the functionality of GMAC3 unit.
I assume that these commits were only tested with a GMAC4 unit.
I have got seen this problem with execution of ptp4l daemon on system with linux 4.11 Kernel.

===============================================================================
root@QuantumXsoc:~ ptp4l -f /etc/ptp.cfg -i eth0 -m
ptp4l[47.928]: selected /dev/ptp0 as PTP clock
ptp4l[47.937]: port 1: INITIALIZING to LISTENING on INITIALIZE
ptp4l[47.938]: port 0: INITIALIZING to LISTENING on INITIALIZE
ptp4l[47.938]: port 1: link up
[ 48.282709] socfpga-dwmac ff702000.ethernet eth0: get valid RX hw timestamp 0
[ 48.316316] socfpga-dwmac ff702000.ethernet eth0: get valid RX hw timestamp 0
[ 48.340260] socfpga-dwmac ff702000.ethernet eth0: get valid RX hw timestamp 0
[ 48.456738] socfpga-dwmac ff702000.ethernet eth0: get valid RX hw timestamp 0
ptp4l[48.457]: port 1: received DELAY_REQ without timestamp
[ 48.488442] socfpga-dwmac ff702000.ethernet eth0: get valid RX hw timestamp 0
[ 48.495599] socfpga-dwmac ff702000.ethernet eth0: get valid RX hw timestamp 0
ptp4l[48.489]: port 1: received SYNC without timestamp
....
================================================================================

I have found two kind of problems and for this two patches (based on the 4.11 kernel) which fix this problem.

1.) PTP_TCR_SNAPTYPSEL_1

The first problem was for my point of view the change of definition PTP_TCR_SNAPTYPSEL_1. I think according the
CYCLON V documention only the bit 16 of snaptypesel should be set. (more information see Table 17-20 (cv_5v4.pdf) : Timestamp Snapshot Dependency on Register Bits)
I believe that the GMAC4 have another necessary definition.

( patch 0001-stmmac-fix-ptp-header-for-GMAC3-hw-timestamp.patch )
================================================================================================
>From 2d54d58dc8548d98572eb5fbfe488ec59b4c0ef5 Mon Sep 17 00:00:00 2001
From: Mario Molitor <mario_molitor@xxxxxx>
Date: Mon, 5 Jun 2017 18:58:49 +0200
Subject: [PATCH 1/2] stmmac: fix ptp header for GMAC3 hw timestamp

According the CYCLON V documention only the bit 16 of snaptypesel should set.
(more information see Table 17-20 (cv_5v4.pdf) : Timestamp Snapshot Dependency on Register Bits)

fixed: d2042052a0aa6a54f01a0c9e14243ec040b100e2
---
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 15 ++++++++++++---
drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.h | 3 ++-
2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 4498a38..13a1ac9 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -471,7 +471,10 @@ static int stmmac_hwtstamp_ioctl(struct net_device *dev, struct ifreq *ifr)
/* PTP v1, UDP, any kind of event packet */
config.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_EVENT;
/* take time stamp for all event messages */
- snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
+ if (priv->plat->has_gmac4)
+ snap_type_sel = PTP_GMAC4_TCR_SNAPTYPSEL_1;
+ else
+ snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
@@ -503,7 +506,10 @@ static int stmmac_hwtstamp_ioctl(struct net_device *dev, struct ifreq *ifr)
config.rx_filter = HWTSTAMP_FILTER_PTP_V2_L4_EVENT;
ptp_v2 = PTP_TCR_TSVER2ENA;
/* take time stamp for all event messages */
- snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
+ if (priv->plat->has_gmac4)
+ snap_type_sel = PTP_GMAC4_TCR_SNAPTYPSEL_1;
+ else
+ snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
@@ -537,7 +543,10 @@ static int stmmac_hwtstamp_ioctl(struct net_device *dev, struct ifreq *ifr)
config.rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
ptp_v2 = PTP_TCR_TSVER2ENA;
/* take time stamp for all event messages */
- snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
+ if (priv->plat->has_gmac4)
+ snap_type_sel = PTP_GMAC4_TCR_SNAPTYPSEL_1;
+ else
+ snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.h b/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.h
index 48fb72f..f4b31d6 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.h
@@ -59,7 +59,8 @@
/* Enable Snapshot for Messages Relevant to Master */
#define PTP_TCR_TSMSTRENA BIT(15)
/* Select PTP packets for Taking Snapshots */
-#define PTP_TCR_SNAPTYPSEL_1 GENMASK(17, 16)
+#define PTP_TCR_SNAPTYPSEL_1 BIT(16)
+#define PTP_GMAC4_TCR_SNAPTYPSEL_1 GENMASK(17, 16)
/* Enable MAC address for PTP Frame Filtering */
#define PTP_TCR_TSENMACADDR BIT(18)